Computer sockets are the interfaces built into motherboards that accept various hardware components. When compatible devices are connected to them, they communicate with the system to provide functionality. Components that use these sockets include dial-up modems, graphics cards, and sound cards.
PCI expansion slots on a motherboard are a type of computer socket.
Standardized protocols allow communication between computer sockets and the devices designed to connect to them. When protocols change, interfaces change names, and manufacturers keep up by designing products that use the latest protocols. In the 1980s, they were called Integrated Drive Electronics (IDE) slots, followed by Enhanced IDE (EIDE) slots.
Modern computer hard drives no longer require socket space on the motherboard.
In some areas, technology has moved beyond these plugs to faster interfaces. Traditional IDE hard drives required wide cables that used parallel technology to send and receive data to the drives. Modern drives use a completely different interface based on serial communication using narrow wires and small pin type interfaces. Not only did this allow for faster drives, but it also saved space on motherboards and improved airflow inside cases.
On average, motherboards have far fewer entry points today than in the past. Many devices are now integrated on the board, reducing the need to add a lot of hardware. In addition to built-in networking and USB and Firewire support, some motherboards also include integrated graphics and sound capabilities. Gamers and audiophiles, however, often continue to opt for state-of-the-art video and sound cards. Each of these devices requires its own computer plug.
While sound cards and many other devices use standard slots, modern motherboards have other inputs, including a dedicated graphics slot. Graphics cards handle large amounts of data and as such the interface is designed to handle larger loads without overloading the central processing unit. There are four main graphics standards for dedicated computer sockets: Advanced Graphics Port (AGP) 4x, AGP 8x, Peripheral Component Interconnect (PCI), and PCI Express (PCIe). The slots are proprietary, meaning an AGP card will not fit into a PCI slot or vice versa.
Knowing what slots a motherboard has when shopping for a new system is a good idea. Users who want the latest and fastest graphics card, for example, will look for PCIe cards and will need a specific connection for it. Some people may also need to install other boards and need to make sure there is room for them.
Additional sockets can be accessed by removing the computer case.
